Sheet feeding device



Feb. 27, G, splEss 2,191,597

SHEET FEEDING DEVICE Filed May 3, 1938 2 Sheets-Sheet 1 Feb. 27, 1940. Gf S|S|ES$ 2,191,597

sEEET4 FEEDING DEVICE Filed May :5, 1938 g snets-sneet 2 Patented .Febl 27, 1940 UNITED v' STATE SHEET FEEDING DEVICE Georg Spiess, Leipzig, Germany Application May 3, 1938, Serial No. 205,788

' In Germany May 4, 1937 4 Claims.

y This invention relates to a sheet feeding device. 4

There are devices of this class known, in which the feed of a sheet from the pile, through an end- 5 less conveyor belt and a stationary checking means pressed againstv the belt at increasing pressure in feeding direction and stressing the elasticity thereof, and anv adjustable pressure means can be regulated in such manner that the sheets are selectively advanced either one behind the other in spaced relationor with any degree of overlapping. Other devices for overlapped sheet feeding employ a regulating gear for varying speed and thereby the degree of overlapping, or they are equipped with two gearings, selectively and alter.- nately engageable by clutches, for the drive of the conveying means of th'e feed table, one of said gearings having a high ratio for retarding the speed of the sheets and the other one a low ratioand invariable speed.

Compared with the known art, the invention has for its object to provide an arrangement for regulating the speed of the conveying means of the feed table in conjunction with periodic retardation of the sheet travel towards the end of the feeding operation so as to permit the transition from overlapped stream to single feeding, and vice versa, without any couplingof the sheet feeding meansy and, further, a reduction of the masses to be accelera-ted and retarded. For this purpose, both high speed feeding means for single feeding and low speed feeding means for overlapped feeding together with the associated adjustable .pressure means are provided on the feed table in such manner, for instance alternately succeeding each other in the direction of travel of the sheets, that thypossess a single joint drive and a control device by means of vvhichthe pressure means, as rolls on balls, are selectively pressed against the low or high speed feeding means to effect a corresponding rate of feeding. It is therefore not necessary any more to disenfeeder with all unnedessary and complicating gage and engage drives, which involves the stop- 5 ping and starting of not inconsiderable masses, as uniform driving of the sheet feeding means is insured and the manner of feeding may be altered without interrupting the feeding drive.

Another feature of the inventionV is that the low` 50 speed and not the high speed conveying means are retarded in known manner for forwarding 'the sheets /to the front gauges and are subsequently accelerated again, the sheets fed at high- E Fig. 4, for overlapping feed.

er'speed being retardedby automatically turning tion over to the slower moving and retarded conveying means. In order absolutely to insure soft sheet contact each sheet may be temporarily arrested by a stop placed in the path of the sheet when the pressure means are lifted off from the 5 high speed feeding means and withdrawn again while the pressure means are set upon the slow speed feeding means. For overlapped feeding the pressure means are fixed in the position at which they contact with the slow speed feedinr,r 10 means and are secured against being acted upon by the control means. l

This reversal by hand of the pressure means regulating the sheet feed to the front gauges is connected with the reversal of the timing roller 15 determining the beginning of the feeding operation. The control of the timing roller or rollers is arranged for single feeding and, for overlapped feeding,` must be adjusted at a position of the `rollers at which they contact with the feeding 20 means.

As far as between the timing rollers and the pressure means vfor the feeding of the sheets to` the front gauges additional pressure means for securing sheet feeding are required, they are pro- 25 vided for thelow speed as Well as high speed feeding means and so arranged that they can be selectively brought into operating or non-operating position. This reversal is preferably connected with the reversal of the previously men- 30 tioned pressure means. Y.

The. feed table according to the invention is preferably of the roller type with alternate arrangement of the slow and high speed conveying means in the direction of travel of the sheet, 35 whereby the reversible arrangement of the pressure means is facilitated.

ByV Way of example, one' form of the invention is illustrated in the accompanying drawings, in

details omitted; and f Figs. 3 and 4 are views on anenlarged scale showing the drive of every firstvr feed roller at low andhigh speed and the arrangements for reversing the pressure means for/single feeding and for their automatic reversal at this lmanner of feeding; more particularly, Fig. `3 showing the adjustment of the feeder for single feeding and 'Ihe sheets are forwarded from the pile I' by a each sheet toward the end of the -feeding opera- 1 separating and feeding device 2 indicated in Fig. 55

i 1 and engaging for instance the rear edge of the sheets to the conveying means of the transmitting table of the roller type whose rollers, beginning at the pile, are alternately designated 4 and 5 in the direction to a machine, for instance the cylinder 3 of a printing machine. The rollers 4 comprising also the first roller with which the rollers 6 coact in known manner to start feeding are driven at a speed corresponding to overlapping feed. Joint driving of the rollers 4 is effected by causing the rollers 4 each provided with a toothed Wheel 1 on one side to mesh in pairs with an intermediate gear 8. The pinion of the first roller 4 is driven by a single revolution control shaft 9 through the medium of a gear periodically effecting retardation and acceleration. This gear comprises a toothed wheel Il) eccentrically secured relative to the driving shaft 9 and transmitting its drive through a planet wheel |I to a toothed wheel ||a .of the first roller 4. The planet wheel II is arranged on the link pin of a joint formed by the arms I2, I3, the arm I2 swinging about the pin of the eccentric wheel I8 and the arm I3 about the axis of the toothed wheel 1 of the first feed roller 4. Owing to this drive, all rollers 4 are periodically retarded and accelerated in the course of a feeding operation, and retardation attains its maximum approximately when a sheet arrives at the front gauges I4.

The rollers 5 are each similarly provided with a Vtoothed wheel I5 on the other side of the table.

The toothed Wheels I5 mesh in pairs with an intermediate gear IE. The rst roller 5 is directly driven from a sprocket wheel Il on the shaft 9 by means of the chain I8.

Above the feed rollers pressure means, as rollers or, as shown in the drawings, balls I9 disposed in retaining cages, are provided in known manner, which can be rendered operative or inoperative in the usual way, not shown. The ball retainers are arranged on a lattice whose longitudinal bars 28 are displaceable in guides 2| in the direction of travel of the sheets, so that by longitudinal displacement of the lattice the balls I9 can be shifted from a roller 4 to a roller 5, and vice versa.

The pressure means cooperating with the feed rollers 4, 5 are reversible, so that thepressure means coacting with the slow 'roller 4 and those coacting with the high speed roller 5 may be alternately brought into and out of operative position. For this purpose, a cage containing a ball coacting with a roller 4 and another cage containing a ball coacting with a roller 5 are arranged in pairs on carriers which are adjustably disposed on a rocking shaft 23 extending transversely over the width of the roller feed table. The rocking shaft 23 is provided on one side of the table with an arm 24 which by an articulated rod 25 is connected with one end of a double-armed roller lever 21 movably disposed at 26. By means of a tension spring 29 the .roll 28 of the lever 21 contacts with the periphery of a cam 30 on the shaft 9.

The pressure rolls 6 coacting with the rst roller 4 and one of the rolls 3| cooperating with the rst high speed roller 5 form a pair connected by a common bearing lever 32, so that by corresponding setting of the lever 32 either one roll 6 can be made to cooperate with the rst roller 4 lever 36 whose roll 31 is drawn by a spring v38 against the circumference of a cam 39. A sheet moved by the cooperation of the roll 6 with the first roller 4 is conveyed at' the higher speed', when the pressure roll 6 is lifted off from the roller 4, owing to the simultaneously established coaction of the roll 3| and of the high speed roller,

ually to be effected reversal of the balls I9 and of the lattice 2|l in the following manner:

The lattice 20 provided with a handle 40 for reversal possesses a stop 4| which coacts with one arm of a double lever 43 movably disposed at 42. The other arm of the lever 43 is connected by a rod 44 with one arm of the roller lever 36 whilst the handle 4|) acts directly upon the'arm 2li of the lever system for reversing the cage carriers 20 to effect stopping. When the control rods are inoperative, the pressure roll 6 rests on the first low speed roller 4 and the balls I9V coacting with the last low speed roller 4 are in operative position. Furthermore, the balls between the first and last roller are adjusted for cooperation with low speed rollers 4.

This adjustment of the 'balls I9 androlls 5 corresponds to overlapping sheet feed which is carried out in the usual manner, for instance by causing a sheet, separated from the pile at its rear edge and advanced, to be caught by the first feed roller 4 and the coacting pressure rolls 5 whose rhythmical control is stopped and to be forwarded to thefront gauges Id by means of the additional feed rollers 4 driven at the same speed, against which the sheets fed in overlapping manner are pressed by the correspondingly adjusted balls I9. At each rotation of the shaft 9 the rollers 4 are retarded and accelerated ink such manner that the sheets strike the front gauges I4 at the lowest; feeding speed of the rollers.

If the sheets are to be fed singly at a distance from one another, the pressure members, by displacement of the grating 20 by means of the handle 40, are so adjusted that they cooperate with the rollers 5, whereby simultaneously vthe` associated rolls 3| are actuated. The process will A then be as follows: y

When a sheet forwarded by the rst feed roller 4 and the pressure rolls 6 is caught by the next feed roller 5 rotating at higher speed and the pressure rolls 3| theref after they have pressed down upon the roller 5, feeding is carried out at the higher speed, since simultaneously the pressure rolls 6 are lifted oif from the roller 4 rotating at lower speed. Toward the end of the feeding operation the cage carriers 2|) are reversed, whereby the balls |9 contained therein are lifted olf fromA .the last high speed roller 5-and the balls cooperating with the last low speed roller 4 are brought into operative position. The

sheet is thus turned over from the high speed feed roller 5 to the low speed roller 4 and forwarded bythe latter roller whose speed is slowed down still more by retarding means to the gauges |4. vThe preceding balls I9 are so adjusted that at this time the sheet is subjected only to the action of the balls disposed inthe carriers 20.

As shown in Fig. 1, near the front gauges I4 preliminary stops 45 having the form of hooked .arms are-secured to a rocking shaft 41 arranged on the underside of a feed plate 4B. The shaft 41 possesses on one side of the table an arm 48 connected by a rod 49 with one arm of a double roller lever 50 arranged at 26 the roller 5l of vwhich is pressed by a tension spring 52 against the circumference of a cam 53. By means of the cam 53 the preliminary'stops 45 are controlled in such manner that they are brought into the path of the sheet when the balls are lifted from the last high speed roller 5 and are swung out again from the path when the balls are placed on the last low speed roller 4. In this way, the preliminary stops 45 insure the adjustment of the sheet travel to the lower`feedlng speed of the roller 4 and timely feeding 'of the sheets to the front 8941868.

It is evident that the reversal of thev feeder from overlapping to single sheet feed, and vice versa, .can thus be effected during operation b y the mere displacement of the handle 40.

I-claim:

1. In a sheet feeding device, a plurality of spaced fast moving conveyor means, a plurality of spaced slow-moving conveyor means alternate- 1y disposed with relation to the fastl moving means, means foralternately accelerating and decelerating the slow moving conveyor means, and a pressure device for pressing fed sheets against the conveyor meansand selectively operable with the fast moving and slow moving conveyor means.

2. In a sheet feeding device, a pluralityof spaced fast moving conveyor means, a plurality of spaced slow moving conveyor means alternately disposed with relation to the fast moving means, means for 'alternately accelerating and decelerating the slow moving conveyor means, ,a pressure device for pressing fed sheets against the conveyor means and selectively operable with the fast moving and slow moving conveyor means, and shifting means for moving the pressure means from one conveyor means to the other. g

3. In a sheet feeding device, a fast moving conveyor means, slow moving conveyor means alternately disposed with relation to the fast moving means, a pressure device for pressing fed sheets against the conveyor means and selectively operable with the fast moving and slow moving con.

veyor means, shifting means for moving the pressure means from Aone conveyor means to the other, and retarding means acting to retard the slow moving means at timed intervals. l A

4. In a sheet feeding device, a fast moving conveyor means, slow moving conveyormeans alternately disposed with relation to the fast moving means, a pressure device for pressing fed sheets against the conveyor means and selectively opl 

